Means for stripping links in a firearm



April 23, 1957 B. DARSIE 2,789,474

' MEANS FOR STRIPPING LINKS IN A FIREARM Filed Nov. 19, 1951 Qvyuem fomBurn .5 II In-Psi E United States 2,79,414 Patented Apr. 23, 1957 MEANSFOR STRIPPING LINKSIN A FIREARM This invention relates to automaticfirearms having a high cyclic rate of fire and more particularly to animproved means for feeding ammunition thereto.

The nature of present day ammunition, the use of disintegrating metalliclinks for holding the rounds; the requisite of rapid feeding, firing,extraction and ejection with the limited operating energy availableimpose requirements for delinking the rounds from the link prior; tochambering of such rounds to diminish the energy expended for saiddelinking.

One of the objects of the instant invention is to provide.

an improved means of delinking present day linked belt ammunition priorto entering the chamber without diminishing the cyclic rate of thefirearm.

Another object of the invention is to provide an improved means offeeding linked ammunition to a rotatable feed wheel that suppliesdelinked rounds to a feedway prior-to said round being chambered by areciprocating member in a firearm.

A further object of the invention is to eliminate'th'e necessity ofhaving the reciprocating bolt member delink the round in the feedwaythereby permitting an uninterrupted and smoother action of suchmember'du'ring the counter-recoil movement when the round is fedforwardly to its chambered position.

Still another object of this invention provides stripping means fordelinking a linked round Without undue strain on the links.

The invention accordingly provides a means of delinking a linked roundfrom a linked belt of ammunition using a link similar to one that isshown and described in Patent 2,480,972, issued September 6', 1949, toR. S. Sanford et al.

These and further objects, which will become more apparent from thefollowing disclosure, are obtained by the unique means illustrated inthe accompanying draw ing in which:

Fig.'1 is a schematic cross-sectional end view of the preferredembodiment of this invention; and

Fig. 2 'is a schematic plan view of the feed wheel, one,

of the teeth of the sprockets being cut away to show the linked roundand stripper.

Q Referring to the drawings, there is illustrated a portion of areceiver 12 having a feedway 14 in the upper part thereof. Aspring-biased cartridge stop 16 is pivotally mounted on feedway 14 ofreceiver 12 to align a delinked cartridge 18 with the axis of a chamberin a barrel (not shown). Associated with the receiver 12 andconventionally mounted on the side thereof, a housing 20 is belt feedingtrough 22, a link chute 24, and a feed Wheel casing 25..

. .65 provided which primarily comprises a cartridge linked Asprocket'or feed wheel 26 is rotata'bly mounted in casing 25 of housing20 parallel to the longitudinal axis of receiver 12 on a shaft 28 forintermittent movement therewith. Peed wheel 26 comprises two spacedapart sprocket wheels positioned to engage the case of a cartridge.Shaft 28 is intermittently rotated by synchronistic means '(not shown)through an are equivalent to the pitch of the links, i. e., the lateraldistance between the center line of adjacent linked cartridges 4%). inthe proximity of the feed wheel 26 a suspended support 38 isprovidedan'd is secured at 32 to wall 34 of casing 25. Support 30 isprovided with a leg portion 36 that is positioned contiguous to an upperwall 38 of trough 22 thereby forming an independent upper portioncooperating with trough 22 to position the linked cartridge 40 prior tobeing fed into feed Wheel 26. Support 30 terminates in a circularportion 42 on the free end thereof contructed to surround shaft 28 andhaving an outside periphery arranged to coincide with the root ofsprocket teeth 68 of feed wheel 26. The periphery of portion 42 y isalso provided with a slightly eccentric cam lobe porvti'on 74. Legportion 36 is provided with an upwardly curved portion 76 disposedforwardly of and adjacent to cam lobe portion 74 for a purpose to bedescribed.

Linked cartridge 40 is reieasably held in a disintegrating metallic link44 being of the conventional type similar .to the link shown anddescribed in the aforementioned Patent 2,480,972 that interlocks withadjacent links thereby forming a linked belt of ammunition. Link 44 isconstructed with a stripper bridge 46 thereby providing a space betweena cartridge case when assembled thereto for a I purpose to be described.On receiver 12 there is with a blade-like end 56 that is constructed topass through the space between the bridge 46 and the case of linkedcartridge 40.

Housing 20 is provided with an inclined bottom Wall 58 that connectstrough 22 and chute 24 thereby forming a continuous passagewaytherebetween. The inclination of wall 58 is approximately parallel to anupper surface 60 of end 56 on stripper 48. I A convexed ramp 62complementary to curved portion 76 of leg 36 is secured tow'all58immediately before and partially under an arcuate surface 64 on end 56of stripper 48. Further down on the inclined Wall 58 a link guide 66 isfastened thereon for a purpose to be described later. .1

Referring to Fig. I linked cartridges 40 are fed into trough 22 with thebridge 46 of link 44 downwardly disposed. As linked cartridge 40 ismoved intermittently along trough 22 by feed wheel teeth 68 of feedwheel 2 6,'bridge 46 of link 44 is cammed upwardly when passing overramp 62 thereby forcing the cart-ridge against the curved portion 76 inleg 36 of support 30 thereby con trolling the entrance of the stripperbetween the cartridge and stripper bridge 46. In the next phase of thefeeding cycle the linked cartridge 40 is moved further along trough22'thereby permitting the arcuate surface 64 to earn the link 44downwardly partially away from the stripper 48 maintains the bridgeagainst the stripper 48 during the final phase of delinking therebyprolonging the time of engagement of the link 44 with the cartridge.During these functions the cartridge is radially moved along an arcuateconfiguration 70 that is a continuation of surface 60 on leg 44 and isdiametrically positioned from the rotatable center of feed wheel 26.While the cartridge is being delinked, it is releasably held against theconfiguration 70 by cam lobe 74 on circularportion 42 of support 30 toeliminateany tendency of the partially delinked cartridge from assumingan improper position in relation to the feed wheel 26 during the finaloperation of entirely removing the link 44 from the cartridge 1%. Camlobe 74 and configuration 70 also holds the cartridge partially linkeduntil the following round has been engaged by teeth 68 of feed wheel 26.The transitory movements of the linkedcartridge 40 over ramp 62 andguide 66 with the cooperation of curved portion 76 and cam lobe 74prevents undue strain on link 44 when such link is being partiallydelinkedfrom cartridge 18 and in conjunction with the contour ofstripper 48 the paths of the link 44 and cartridge 18 are bothcontrolled during stripping in such a manner that the clamping elementsof the link are of a great assistance in maintaining control of thecartridges until stripping is nearly-completed. Link 44 when free ofcartridge 18 falls by gravity down chute 24. Cartridge 1s duringsuccessive movements of the feed wheel 26 is carried upwardly by suchfeed wheel until the cartridges are cammed into feedway 14 by apivotally mounted spring biased lever mechanism 72 actuated by mechanism(not shown).

While there is shown a particular embodiment of this invention, it willbe understood, of course, that I do not wish to be limited thereon,since many modifications may be made and therefore it is contemplated inthe appendent claims to cover any such modifications as fall within thetrue spirit and scope of this invention.

I claim:

1. In a firearm having a transverse feedway, a housing fixedly securedto the firearm adjacent the entrance of the feedway, and rotatablesprocket means mounted in the housing for advancing a belt of linkedcartridges therethrough into the feedway, the combination of a feedtrough extending into the housing to intersect the bottom portion of therotative path of the sprocket means, a link chute extending upwardlyinto the housing to communicate with said feed trough, a stripperfixedly secured to the firearm and having an outwardly projectingblade-like portion extending into said feed trough beneath the sprocketmeans and into the path of the incoming linked cartridges, cam means insaid feed trough for raising a linked cartridge into position to assureentry of said blade-like portion of said stripper between the link andthe cartridge, said bladelike stripper portion having an arcuatelyformed underside for camming the link away from the cartridge during thecontinuation of the feeding movement thereof, a support fixedly securedat one end thereof in the housing to extend inwardly therein over saidfeed trough and partially encircle the sprocket means, an eccentric camon said support for guiding a partially stripped cartridge along theupper surface of said blade,-

like stripper portion and thereby prolonging the interval of actualstripping operation, and cam means in said feed trough adjacent thecommunicating end of said link chute operative on the partially strippedlink to maintain contact thereof with the cartridge associated therewithuntil the following successive cartridge is positively engaged by therotating sprocket means. 7 j

2. In a firearm having a transverse feedway, a housing fixedly securedto the firearm adjacent the entrance to the feedway therein, saidhousing having a feed passage extending along the bottom thereof toterminate in a downwardly extending link chute, a feedwheel rotatablymounted in said housing and having a plurality of sprocket I teethdepending into said feed passage for advancing a belt of linkedcartridges therealong, alinkstripper secured to the firearm above'saidlink chute and having v a projecting bladelike portion extendingoutwardly along said feed passage into the path of the advancingcartridge belt for entry between each cartridge and the link associatedtherewith, and cam means in the top and bottom of said feed passage forsuccessively forcing the cartridge and the link associated therewithtoward each other during the respective stripping movements thereof toprolong the engagement therebetween until positive engagement of saidsprocket teeth with the next following cartridge.

3. In a firearm having a transverse feedway, a housing fixedly securedto the firearm in alignment with the entrance to the feedway, saidhousing having a feed passage therethrough including a feed troughextending along the bottom thereof and a downwardly extending link chutecommunicating "with said feed trough, a feedwheel rotatably mounted insaid housing and having a plurality of sprocketteeth successivelyengageable with the ;car tridges in a linked belt for advancing the beltalong said feed trough, a support member having one end thereof fixedlysecured in said housing and extending above and parallel to said feedtrough to terminate at the free end thereof in a feedwheel encirclingportion, a link stripper fixedly secured to the firearm above said linkchute and having an arcuate upper surface cooperating with said sprocketteeth to guide the cartridges upwardly toward the transverse feedway inthe firearm, said link stripper :having a projecting bladelike portionextending outwardly along said feed trough into the path of theadvancing cartridge belt for entry between each cartridge and the linkassociated therewith, said bladelike portion having an arcuate lowersurface for initiating the stripping of r the cartridge from the linkassociated therewith, a cam lobe portion on the feedwheel encirclingportion of said support member for camming the cartridge downwardly outof the rotative path imparted thereto by said sprocket teeth and intothe link associated therewith to prolong the stripping engagementtherebetween, and cam means in the bottom of said feed trough adjacentthe entrance to said link chute for forcing the link upwardly toward thepartially stripped cartridge to continue to prolong the strippingengagement therebetween until after positive ent gagement of saidsprocket teeth with the next following cartridge thereby preventing anydiscontinuity in the feeding movement of the cartridge belt.

' 4. In a firearm having a transverse feedway, a housing fixedly securedto the firearm at the entrance to the feedway therein, said housinghaving an entrance for a belt of linked cartridges and a feed troughextending along the bottom thereof in communication with said entrance,a feedwheel rotatably mounted in said housing and having a plurality ofsprocket teeth successively engageable -with the cartridges foradvancing the belt along said feed trough, a support member having oneend thereof fixedly secured in said housing and extending above andparallel to said feed trough to terminate at the free end thereof in afeedwheel encircling portion, a link stripper fixedly secured to thefirearm at the end of said feed trough and having an arcuate uppersurface cooperating with said sprocket teeth to guide the cartridgesupwardly toward the transverse feedway in the firearm, said link Istripper having a projecting bladelike portion extending outwardly alongsaid feed trough into the path of the advancing cartridge belt, a convexcam disposed in the bottom of said feed trough adjacent the projectingend of said link stripper for lifting each linked cartridge intoposition to assure entry of said link stripper end between 'thecartridge and the link associated therewith, said support member havinga concave portion therein in coaxial al gnment with said convex cam topermit the lifting of the linked cartridge, said bladelike stripperportion having a convex underside surface adjacent the free end thereoffor forcing the cartridge link out of engagement with the cartridgeassociated therewith, a camlobe portion on the feedwheel encirclingportion of said support member projecting beyond the root periphery ofthe 2,789,474 5 6 sprocket teeth for camming the cartridge downwardlyout discontinuity in the feeding movement of the cartridge of therotative path imparted thereto by said feedwheel belt. and into the linkassociated therewith, and an arcuate cam surface in the bottom of saidfeed trough adjacent References Cited in th file Of this patent the exitthereof for forcing the link upwardly out of the 5 UNITED STATES PATENTSstripping path thereof, said cam lobe portion and said arcuate camsurface being disposed in adjacent relation 2453786 Dixon 1948 toprolong the stripping engagement between the link FOREIGN PATENTS andthe cartridge until said sprocket teeth eflect positive 555 267 GreatBritain Aug 13 1943 engagement of the next following cartridge toprevent 10

